In some cases, an ailment or medical condition may affect the quality of a patient's sleep. For example, neurological disorders may cause a patient to have difficulty falling asleep, and may disturb the patient's sleep, e.g., cause the patient to wake frequently during the night and/or early in the morning. Further, neurological disorders may cause the patient to have difficulty achieving deep sleep stages.
Examples of neurological disorders that may negatively affect patient sleep quality include movement disorders, such as tremor, Parkinson's disease, multiple sclerosis, or spasticity. Other examples of neurological disorders that may negatively affect patient sleep quality include sleep disorders, such as, rapid eye movement behavior disorder (RBD), in which case, a patient may act out dramatic and/or violent dreams, shout or make other noises (e.g., grunting) during the rapid eye movement (REM) sleep. In each case, the uncontrolled movement associated with such sleep and movement disorders may cause a patient to have difficulty falling asleep, disturb the patient's sleep or that of a sleep partner, or cause the patient to have difficulty achieving or maintaining deep sleep stages. In case of RBD, for example, a patient can cause injury to themselves or others.
Drugs are often used to treat neurological disorders. In some cases, neurological disorders are treated via an implantable medical device (IMD), such as an implantable stimulator or drug delivery device. In some examples, the treatments for neurological disorders may themselves affect sleep quality. Further, in some cases, poor sleep quality may increase the symptoms experienced by a patient. The condition of a patient with such an ailment may progressively worsen when symptoms disturb sleep quality, which may, in turn, increase the frequency and/or intensity of symptoms of the patient's condition.